Internal-combustion engine with variable compression ratio



Aprll 19, 1949. o. E. ROSAEN 2,467,568

INTERNAL-COMBUSTION ENGINE WITH VARIABLE COMPRESSION RATIO Filed July 25, 194e s sheets-sheet 1 Q nn O42 -1 To SUMP PRESS/KE /NLEr 7a ,vu/1,094

IN VEN TOR. Oscar f. F0506 A TTONE YS April 19, 1949. o. E. RosAEN INTERNAL-COMBUSTION ENGINE WITH VARIABLE COMPRESSION RATIO Filed July 25, 1946 3 Sheets-Sheet 2 INVENToR. Oscar E. osae/v A7' TOR/VEYS April 19, 1949- o. E; RosAEN 2,467,568

INTERNAL-COMBUSTION ENGINE WITH VARIABLE COMPRESSION RATIO Filed July 25, 1946 5 Sheets-Sheet 3 FIG. 5.

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j; .su/w 0560/' E. fosas/7 Patented Apr. 1 9, 1949 INTERNAL-COMBUSTION ENGNE WITH VARIABLE COMPBESSION RATIO Oscar Rosaen, Detroit, Mich., assigner of onethird to Borge Rosaen and one-third to Nils Rosaen, both of Detroit, Mich.

Application July 25, 1946, Serial No. 686,085

The present invention relates to internal combustion engines and more specifically to the combustion chambers of such engines.

Among the objects of the invention is an engine provided with combustion chambers which are automatically variable in size in accordance with load conditions.

Another object is hydraulic means for varying the capacity of the combustion chambers and maintaining the movable element or elements during the high pressure periods.

Another object is hydraulic means for the purpose indicated which is controlled in its operation by conditions of pressure in the intake manifold.

Still other objects and advantages Will be apparent to those skilled in the art upon reference to the following description and the accompanying drawings in which Fig. l is an end elevation of an internal combustion engine equipped with the present invention.

Fig. 2 is a sectional view on a vertical plane transverse-of the engine and passing through one of the cylinders and through the control hydraulic cylinder.

Fig. 3 is a section on line 3-3 of Fig. 2.

Fig. 4 is a diagrammatic view indicating the hydraulic iiuid flow.

Fig. 5 is an elevational view of al detail of construction.

Fig. 6 is a section on line 6-6 of Fig. 5.

Fig. 7 is a section on line 'l--l of Fig. 2.

In the drawings, there is shown an internal combustion engine which, with certain exceptions "notedbelow, may be conventional from the tops fof the cylinders down. That is, it may have the usual water-jacketed cylinder block l0, crankcase Il, intake and exhaust manifolds I2 and i3, etc.

The engine shown is provided with a conventional drive belt l5, driving the fan I6 and water pump, and the generator l'l, and in addition to these accessories, in the present invention, the same belt may be used to drive a hydraulic pump 2G.

This latter pump 20 may be any suitable type, reciprocating or rotary but should be capable of delivering an excess of fluid under a suiciently high pressure.

As indicated in Fig. 4, the pump 20 may`take oil from the crankcase I l or other suitable reservoir of the engine through a yconduit 2l and deliver it through a pressure relief valve 22 and conduit 22A to a manifold 23 from which individual conduits 24 lead to the superstructure 2 Ciaims. (Ci. 12S-48) 2 25 of the engine. From the latter, the oil will be returned through conduit or conduits 26 to the crankcase or reservoir.

Referring now more particularly to Figs. 2 and 3, the engine shown is of the L-head type 'with the combustion chamber offset from the cylinder 30 and above the valves 3 l.

The combustion chamber is shown as a short cylinder 32, preferably jacketed as at 32A, and containing a piston 33, and is so located that it extends over a portion of the cylinder 30 and over the valves 3|, being cut away as at 33A for valve clearance when it is in its lowest position. The

4piston 33 may also be provided with a groove or passageway 33B (see Fig. 3) affording com-- munication between the spark plug pocket 30A and the valve pocket when the piston 33 and the lower piston 30B'are in the position of their closest approach.

The piston 33 is, as shown, hollow-and provided with a cover plate 3 held in place by suitable screws, which cover plate is provided with several openings allowing free communication between the interior of the piston and the cylinder space above it. Three or more of such openings serve also for the passage of bolts 36 which extend into the piston and carry springs 36A which, acting between the bolt heads and the plate 34, tend to lift the pistons, these bolts 36 being anchored at their upper ends in a perforated plate 3l topping the cylinder 32.

The plate 34 is also provided with a relatively large central opening to receive a sleeve member 38, shown in Figs. 5 and 6. This member consists of a sleeve of which the mid portion is enlarged as at 32A and provided. with a plurality of openings 38B. The enlargement 38A is seated in the underside of plate 34 and held resilientl therein by a suitable spring 38C.

The lower end of sleeve 38 is closed by a suitable plug and provides space for the movement of a hollow rod 39 arranged to flt slidably in the sleeve and isy normally positioned with its lower end at or below the bottom of sleeve enlargement 38A, forming a valve therewith.

The hollow rod 39 extends up through the top plate 3l inlet chamber 40 and outlet chamber 4l and through the cover plate MB of the latter and is provided at its upper end with an eye or other means for pivotal connection with a link 4,2. At that portion of the rod within the outlet chamber 4l, the rod is provided with openings MA aording :communication between the interior of the rod and the chamber 4l. It is preferred to support the rod 39 in a sleeve 39A eX- memos tending down through both chambers ll and Il and forming a suitable bearing for the rod.

The link I2 connects the rod 39 to a short ann 43 fixed to a shaft 44 extending over the several cylinders and of course carrying as many of the arms 43 as there are cylinders.

Y The shaft 44 is mounted in suitable bearings and is oscillatable by means of a long arm 45 keyed thereto and linked as at 46, to a piston rod 41 which extends into a cylinder I8 and is connected to a suitable piston 49|therein. Surrounding the rod 41 and acting between the cover plate 52 of the cylinder I3 and tension adjusting nuts 63 carried by the rod is a suitable spring Il.

The cover plate 52 of the cylinder is perforated as at IZA, and the space under the piston I! is connected through a conduit 53 to the intake manifold I2 of the engine.

In the operation of the invention, assuming the engine to be not running and all oil spaces filled, the spring 5| will have moved the arm I5 up to its extreme upper position. The rod 39 will therefore have moved up and thereby opened communication between the interior of piston 33 and outlet chamber 4| through the rod, so that the springs 36A will have moved the piston 33 to its upper position, thereby increasing the capacity of the combustion chamber.

When the engine is cranked for starting and before oil pressure is built up in the manifold 23, suction in the intake manifold l2 begins to act on piston 49 but the movement of piston 33 is little or none until suilicient oil pressure develops. As soon, however, as the engine begins to operate, the oil pressure in manifold 23 forces the pistons 33 down and positions them in accordance with the intake manifold pressure, and adjusts such positions with changes in the throttle position.

When the engine is running but with the throttle closed to idle position, the lowest pressure exists in the intake manifold and consequently piston 49 and valve number 39 are in their lowest positions. Also, pump 20 is supplying oil to the chamber 40 and top of piston 33.

With these parts in such positions, valve 33-33 is closed and all of the oil delivered by the pump flows through relief valve 22 back to the sump.

When, however, pressure in the manifold increases, piston 49 rises and lifts valve number 39 from its seat thus allowing escape of some of the oil into chamber 4i and also allowing the springs 33A to lift the piston 33. This movement of piston 33 tends to or does close the valve 33-39 again, but the piston 33 has assumed a higher position corresponding with the position of piston 49.

In actual running, the valve 33-39 will seldom, if ever, be entirely closed.

I claim:

1. In an internal combustion engine, a combustion chamber having a movable wall in the form of a hollow piston, a sleeve therein, said sleeve being closed at its inner end and being axially located and provided with openings affording communication between the hollow piston and `the interior of saidsleeve, a hollow rod slidablein said sleeve and extending to beyond said openings, a pressurechamber adiacent said piston and communicating with the chamber therein, and outlet chamber disposed above said pressure chamber, said` hollow rod passing through said chambers and having openings into said outlet chamber, an oil pump actuable by said engine and adapted to supply oil under pressure to said pressure chamber whereby to move said piston in a direction to decrease the capacity of said combustion chamber and at the same time open the sleeve openings to allow oil to ilow through said rod to said outlet chamber, means for positioning said rod whereby to control movement of said piston and means affected by intake manifold pressure to control said positioning means.

2. Superstructure for an internal combustion engine including a cylinder having its lower end partially overlying a working cylinder and providing a combustion chamber therefor, a piston in said first mentioned cylinder, means for supplying oil under pressure to said first mentioned cylinder above said piston, resilient means for resisting the downward movement of said piston and valve means for controlling the outow of oil from said first mentioned cylinder, said valve means consisting of two cooperating members, one of which is carried by said piston and the other of which is controllably movable axially of the first mentioned cylinder.

oscila E. Roem.

REFERENCES CITED The following references are of record in the ille of this patent:

UNrrED STATES PATENTS Name Dato Schmidt Jan. 4, 1916 Wilson Aug. 16, 1927 Gaty May 12. 1936 FOREIGN PATENTS Country Dato Germany Oct. 12, 1907 France May 8, 1936 England July 26, 1936 Australia Sept. 7, 1939 Number 

